the maximum pressure and the capacity in the fire tube boiler are usually depends on the model design and specified by the manufacturers in the manufacturer manual.
fire tube & water tube . high pressure and low pressure. low capacity and high capacity.
In a fire tube boiler, the water surrounds a set of tubes through which the fire and the products of combustion travel (as opposed to a water tube boiler, in which the water travels through the tubes, and the fire surrounds the tubes).The HVAC Veteran
So that it can withstand the external pressure of the water pushing inwards to crush the furnace.
The stay tubes basically hold the boiler together, they are thicker than the ordinary tubes and generally dont need to be replaced as often.
You will find it in any mechanical engineering heat transfer book
fire tube & water tube . high pressure and low pressure. low capacity and high capacity.
there are two types of boilers water tube and fire tube. fire tube boilers are divided in to two categories vertical and horizontal. this according to the construction of fire tubes. it is said that vertical boilers are inefficient than horizontal boilers. The vertical boiler is small capacity, and horizontal boiler is higher capacity, well, the horizontal boiler have many types according the drums, there are single drums boiler, and double drums boiler, while, the single drums boiler have fire tube boiler and water and fire tube boiler, double drums boiler is usually water tube boiler.
The words are literal , a water tube boiler is water inside the tubes with hot gases surrounding them and a fire tube boiler are got gases within the tubes with water surrounding them.
the advantage is the design is complicated
In a fire tube boiler, the water surrounds a set of tubes through which the fire and the products of combustion travel (as opposed to a water tube boiler, in which the water travels through the tubes, and the fire surrounds the tubes).The HVAC Veteran
Fire tube and water tube. Steam Boiler and Water Boiler.
The difference between the two is that the Water tube boilers are safer and last much longer than the fire tube boiler. Their size is also larger and have a faster recovery time. However fire tube boilers have a low cost.
water
So that it can withstand the external pressure of the water pushing inwards to crush the furnace.
Beacose its boilng
A simple vertical boiler is a type of fire-tube or water-tube boiler where the boiler barrel is oriented vertically instead of the more common horizontal orientation.
The answer is in the name. Boilers are made with a "tube - in - shell" construction, and the name implies what is in the tube. In a water tube boiler, the water circulates through the tubes, and the burner is usually under them. Most of the time, the "shell" of this style of boiler would not be watertight. A fire tube boiler has a watertight outer jacket with tubes through the center of it. The flame is shot through the tubes.